Effect of Preoperative Body Mass Index on Postoperative and Long-Term Outcomes in an East Indian Gastric Cancer Cohort.

ABSTRACT

BACKGROUND: Gastric cancer is a global health concern with varying clinical outcomes. This study aims to investigate the influence of preoperative Body Mass Index (BMI) on survival in patients who underwent curative resection for gastric cancer in Eastern India. METHODS: Data from a prospectively maintained Surgical Oncology database were analysed for patients who underwent curative resection for primary gastric adenocarcinoma between May 2016 and March 2022. Patients with incomplete data were excluded. Preoperative BMI was categorised into three groups Underweight (< 18.5 kg/m2), Normal (18.5-22.9 kg/m2), and Overweight/Obese (=23 kg/m2). Clinicopathological details, short-term outcomes, and long-term oncological outcomes were assessed. Statistical analysis included survival estimates, Cox proportional hazard models, and subgroup analysis. RESULT: Of 162 patients, 145 met the inclusion criteria. Patients were predominantly male (68%) with middle or lower socioeconomic status. No significant differences amongst BMI groups were observed in performance score, tumour grade, clinical stage, or short-term outcomes. Postoperative complications and 30-day mortality were similar. However, underweight patients had poorer 4-year disease-free survival (DFS) compared to overweight/obese patients (14.3% vs. 39.7%, p = 0.03). Overweight/obese patients showed significantly better 4-year overall survival (OS) than underweight patients (47.8% vs. 20.4%, p = 0.03). CONCLUSIONS: In Eastern Indian gastric cancer patients undergoing curative resection, preoperative higher BMI (overweight/obese) was associated with better long-term survival. Understanding these findings could guide tailored interventions to improve outcomes in this population.